1. Related Applications
Claim of priority is made for the present invention pursuant to 35 U.S.C. .sctn.119 to obtain the benefit of the earlier filing dates in Japan of the following Japanese applications:
"Recording Tape Information Code System," filed Feb. 20, 1981, application No. 56-23928; PA0 "Remote Control Code System," filed Feb. 20, 1981, application No. 56-23929; PA0 "Recording Tape Residual Quantity Sensing Apparatus of Automatic Telephone Answering Device," filed Feb. 20, 1981, application No. 56-23930; PA0 "Automatic Answering and Recording Apparatus," filed Feb. 20, 1981, application No. 56-23931; PA0 "Message Selection System for Automatic Recording Apparatus," filed Mar. 23, 1981, application No. 56-41893; PA0 "Latest Recorded Information Discriminating System," filed Mar. 23, 1981, application No. 56-41894; and PA0 "Message Recording System," filed Mar. 31, 1981, application No. 56-47688.
2. Field of the Invention
The present invention relates to telephone answering devices, and more particularly, to a telephone answering device which is fully controlled by a microprocessor. In addition to controlling all the standard telephone answering device functions, the microprocessor enables the implementation of a variety of novel features which significantly increase the usefulness as well as convenience of a telephone answering device. These additional features are accomplished without adding significant complexity to the design of the device.
Telephone answering devices often use two separate cassette-type tape recorder/playback apparatuses (hereinafter "tape drives"). One tape drive is used to play back a prerecorded outgoing message or announcement from one of the cassettes when a call is received. The announcement typically states that the person is unavailable to come to the phone and that a message may be recorded at the sound of a tone. When the caller hears the tone, he then dictates his message into the phone, which is recorded by the second or incoming message tape drive onto the second cassette tape. After the incoming message is completed (or when the time allotted for the message has expired), the incoming message tape drive stops. The answering device then waits until a new incoming message is received at which time the incoming message tape drive is restarted. Each incoming message is sequentially recorded on the incoming message cassette tape until the incoming message tape is full or until the user returns to play back the recorded messages. To listen to the recorded messages, the user rewinds the incoming message tape to the beginning of the tape and then places the second tape drive into the playback mode. Each recorded message is then sequentially played back in the order in which it was received.
3. Description of the Prior Art
It is often highly desirable to know the exact date and time that a particular message is received. This information is generally not provided by typical prior art telephone answering devices. For example, Sato U.S. Pat. No. 3,925,617 suggests automatically recording a voice time-of-day signal from a radio onto a single track incoming message tape at preset intervals (e.g., every 30 minutes). This time recording is inhibited when an incoming message is being recorded. Thus the incoming message tape apparently contains consecutive voice time signals interspaced between the recorded incoming messages. The time signal is not triggered by receipt of a call, hence it is not possible to determine the exact time within the preset intervals that a particular message was received. Another device which records time-of-day signals is suggested in Boyer U.S. Pat. No. 3,372,240.
It is an object of the present invention to provide a telephone answering device which automatically records date and time information indicating when a message is received, and which displays such time and date as that particular message is being played back.
Another problem encountered with previous telephone answering devices is that after all the messages have been played back, the user often desires to play particular messages again which he may have found interesting. In order to do this with many prior art answering telephone answering devices, the user rewinds the incoming message tape to where he believes is the approximate location of the desired message. The tape is then played back at that point until the user recognizes whether or not the message being played is the desired message. If not, the user then rewinds or fast forwards the message tape a certain distance and plays the tape again. The user continues in this trial and error method until the desired message is found. The user then attempts to find the beginning of that message.
In order to aid the user in finding a particular message, it has been proposed in Zarouni U.S. Pat. No. 3,141,931 to prerecord message numbers, usually by voice, on a separate track of the incoming message tape. However, since the message numbers are prerecorded, this necessitates that the space provided for each message on the incoming message tape be fixed. Since actual messages are variable in length, the unused tape between messages is wasted. Furthermore, during playback, the user is required to wait during this dead space for the next message to begin or otherwise must interrupt the playback mode to fast forward the incoming message recorder to the beginning of the next message. In addition, the user is still required to monitor the message number track and rewind and fast forward until the desired message is found.
Other telephone answering devices have mechanical counters which incrementally move a message number wheel each time a message is received. When a playback key is depressed, the tape is automatically rewound to the beginning of the tape which resets the message number wheel to message number "one." The tape is then played back with the message number wheel indicating the message number of each message as it is played. Again, the user must manually rewind and fast forward until the desired message is found.
It is an object of the present invention to provide an improved telephone answering device which can automatically locate and playback messages preselected by the user.
It is another object of the present invention to provide an improved message numbering scheme for a telephone answering device for automatic control of the playback of the messages.
The functions of "playback", "rewind", "fast forward", "stop", etc. are typically controlled by keys or switches physically located on the telephone answering device itself. Some answering devices have the capability of having a few of these function operated from a remote location. The user, when absent from his answering device, can call and control these functions of the device over the telephone. Prior art telephone answering devices are typically controlled over the telephone by a set of audio tones each of which has a unique frequency. Each function is usually assigned one frequency (or combination of frequencies). The telephone answering device, upon receipt of a particular frequency (or combination of frequencies) activates the corresponding function.
The tones are typically generated by depressing the buttons of a "touch tone" phone (Zarouni U.S. Pat. No. 3,141,931 and Murata U.S. Pat. No. 3,904,826 et al.) or by a separate remote control unit or "beeper" which the user places near the mouthpiece of the phone. In either case, the telephone answering device usually has relatively complex tone discrimination circuits to determine which tone of the set of control tones was sent, and to activate the corresponding function. Generally, the more functions that are controlled, the greater the number of tones required and consequently, the greater the complexity of the tone discrimination circuits in the telephone answering device.
It is an object of the present invention, to provide a relatively simple system for operating a telephone answering device from a remote location yet which is capable of controlling a large number of telephone answering device functions.
In order to prevent unauthorized persons from playing back the recorded messages over the telephone, many telephone answering devices require the receipt of a particular security code before the telephone answering device will respond to remote control. For example, Hoven U.S. Pat. No. 4,196,311 suggests transmitting a binary security code from the remote control unit to the telephone answering device. The particular binary code sent is set by the positions of a number of switches located on the remote control unit. The telephone answering device has a similar number of switches which must be set to the identical positions of the switches on the remote control unit. Thus if one or more switches on the telephone answering device is inadvertently set incorrectly, then the telephone answering device can not respond to the remote control unit.
It is an object of the present invention to provide a simple method of entering a new security code which is displayed as it is entered.
It is another object of the present invention to provide a remote control unit and telephone answering device system in which a new security code entered into the telephone answering device is automatically transmitted to the remote control device as well.